I have an 04 LJ and am planning a rubicon tcase swap. I have been searching around for a write up, no luck finding one that is LJ specific. Wondering if anyone has done it or knows the answers.

I already have a body lift with a flat skid. Currently the skid is dropped 1'' and I took out my budget boost to make up the difference in angle for the stock DS so I could still run it prior to the tcase swap. I know I will need to get a longer rear drive shaft since the rubi tcase has the SYE but I'm wondering about the front DS and any other possible issues? I intend to take out the 1'' drop on skid and be completely flat once new tcase goes in.

From my understanding everything should be a direct bolt in with exception to the drive shafts? I've never had to modify a DS or buy a new one due to another mod changing the distance from tcase to pinion yolk, recommendations on where to go for ds modification or purchase of new and any advice would be appreciated.

The flatness to frame/clearance of your skid could be an issue depending on your trans. Getting the T-case up enough before hitting the tub could be a issue if your running the OD auto trans and trying to keep that trans pan above the frame rail bottom.

I'm assuming your running a 1BL?? You might save your self some time and start fitting that T-case and it's connections, breathers, and linkage on your tub while fitting your skid before you get rear drive shaft. Your going to need a double cardon shaft for the rear if your running a flat skid anyway so you might as well just see where your DS angle is at that WB and get it once if ya can, might even get super lucky and get that BB back on without changing your rear pinion angle and just getting a rear shaft...but I doubt it.

FWIW you should be able to move that T-case up from it's factory/stock position (with a BL) a good 1.5 inches and use a factory Rubi/LJ DS without a problem.

I started in on this saturday. Took off the flat skid and supported everything to start unbolting the tcase. Once I had it out the Rubi tcase went right in. I picked up a tcase mount today since the old one had a bolt sheared off. As of now the tcase is bolted to trans and waiting to bolt/plug everything back in. I didn't measure the body lift, but I would guess it to be more than 1'' and was installed when I bought the LJ. From what I see at this point everything should bolt right in and the skid up tight to the frame. I was reading up on junk yard upgrades and found a guy who bought a front DS from a junk yard explorer, had it shortened/balanced and used it for his rear, ran him $130 bucks. I'm thinking of going that route myself. As for front DS, I'll wait and see what happens once all is in right and tight.

The flatness to frame/clearance of your skid could be an issue depending on your trans. Getting the T-case up enough before hitting the tub could be a issue if your running the OD auto trans and trying to keep that trans pan above the frame rail bottom.

I'm assuming your running a 1BL?? You might save your self some time and start fitting that T-case and it's connections, breathers, and linkage on your tub while fitting your skid before you get rear drive shaft. Your going to need a double cardon shaft for the rear if your running a flat skid anyway so you might as well just see where your DS angle is at that WB and get it once if ya can, might even get super lucky and get that BB back on without changing your rear pinion angle and just getting a rear shaft...but I doubt it.

FWIW you should be able to move that T-case up from it's factory/stock position (with a BL) a good 1.5 inches and use a factory Rubi/LJ DS without a problem.

your front DS should be fine.

I'm curious if I will be able to use front, it just seems like a lot of lift on the tcase for it to reach the same. If so I'll be happy.

Have you tried mounting up the front driveshaft yet? I thought that the 231 has a 1310 front output and the Rubi T-case has a 1330. I know that you can get a yoke to make the rubi 1310. Just wondering.

Have you tried mounting up the front driveshaft yet? I thought that the 231 has a 1310 front output and the Rubi T-case has a 1330. I know that you can get a yoke to make the rubi 1310. Just wondering.

Not yet. I may get to it tomorrow morning otherwise it won't be till monday morning. I would have today but I had to get myself 20 chickens and a coop from a coworker. Can't lose with free laying hens and a coop.

I don't have a body lift, but I do have a Full Traction LA kit. It has a very flat skid plate, and I had to do some clearancing with a mallet, towards the drivers side floor.

The only other thing you need to do is change the shifter linkage. Or, do what I did and modify what you have. I bent mine, and then gusseted it.

Everything looks good so far, the wire harness had one connection that doesn't plug together I think its for the dash light. Didn't check. Hoping to call around and find a front shaft from junk yard to use for rear.

Have you tried mounting up the front driveshaft yet? I thought that the 231 has a 1310 front output and the Rubi T-case has a 1330. I know that you can get a yoke to make the rubi 1310. Just wondering.

The front output on the rubi tcase works with the stock drive shaft. It's a 1310. However the rear is 1330.

The drive shaft lentghs should be the same. I put a 1310 yoke on the front and used my factory regular front drive shaft. The rear I ordered one with a 1310 flange adapter. So all my u-joints were still 1310.

2005 rubicon. Unless its the ubolt style yoke and not the strap, i just put the front ds up to it to check the fit, never bolted it in. That comes in the morning after I pick up my new yoke for rear axle.

The drive shaft lentghs should be the same. I put a 1310 yoke on the front and used my factory regular front drive shaft. The rear I ordered one with a 1310 flange adapter. So all my u-joints were still 1310.

I'm upgrading the rear axle yoke to 1330 so my rear DS is all 1330 ujoints. I didn't think the front output on the tcase would be 1310 but the seller may have put it on, he said he was looking up some part numbers to make things easier for my install.

When I did this swap I picked up a LJ Tom Woods driveshaft with the adaptor that bolts to the Rubi balancer. I would suggest getting the Novak cable shifter to prevent binding. I will be installing mine as soon as I get my flat skid finished. For now I cut approx 1" out of my shifter linkage, welded it back together and did some testing to see how it would shift. A bit of trial and error and it shifts fantastic.
There is a good chance you have the 1 1/4" which seems to be the norm with a 1" MML.
I also cut my front driveshaft boot off to make sure it would extend as far as it needed to without causing issues.
Once you get it installed and you test out the 4:1 you will be amazed at the difference.
This was one of the best mods I've done to my LJ and it was cheap, but I got lucky with my parts and found some killer deals.

Look at the Tatton driveshaft for a bit more money you will have a much more stout driveshaft.
Good luck with the swap.

Look at the Tatton driveshaft for a bit more money you will have a much more stout driveshaft.
Good luck with the swap.

I wouldn't say that. This Tatton failed right at where the rear yoke was welded on. No scrapes, dents or anything of the sort on the drive shaft. After looking at it, it was easy to see that the weld was cold (IE no heat marks on the tube). Also it was ground down to being almost smooth, which goes along with shitty welds in most cases.

If I were to recommend a drive shaft it would from http://oliversdriveshaft.com/ quick turn around, cheap shipping, and more than fair prices. Not to mention Dave was able to build and balance a 2.5"x.250" DOM rear drive shaft for me. Runs true and smooth on the high way and is proof!

That sucks about the Tatton driveshaft. My buddy Joe runs one without any problems. Hopefully they have better welds now.
Good to know about another source for driveshafts. I'm very happy with my TW driveshaft, but I got a great deal on it when the guy went a different direction with his build.